Amphibromus neesii Steud., Syn. Pl. Glumac. 1: 328 (1854).

Helictrotrichon neesi (Steud.) Stace, . T: Van Diemen's Land, Gunn 995; lecto: K, n.v.

Illustrated in: Jacobs & Hastings, in Harden ed. (1993) Fl. New South Wales 4: 597.

Vegetative form. Perennial, erect, occasionally rhizomatous or caespitose. Basal culm internodes not swollen. Culms to 150 cm high, 2-4 noded. Mid-culm nodes glabrous, exposed, constricted. Mid-culm internodes hollow, glabrous, terete or compressed (slightly). Leaves non-auriculate. Basal leaf sheaths glabrous or scabrous (slightly), with the veins equally striate. Ligule (4.5-)6.5-8(-10) mm long, not lobed, membranous, smooth, acute, entire (becoming lacerated with age). Leaf blades flat or involute, linear, to 370 mm long, 2-4 mm wide; adaxially scabrous (on the veins), channelled; abaxially glabrous to abaxially scabrous, with the veins equally striate.

Reproductive organization. Plants bisexual. Incomplete spikelets absent (?). Inflorescence of cleistogamous spikelets, or chasmogamous spikelets (with cleistogamous and/or chasmogamous florets).

Inflorescence. Inflorescence a panicle, erect, open or contracted. Rachides 370 mm long (?), terete, glabrous (becoming scabrous toward apex). Primary inflorescence branches solitary or clustered, appressed (often flexuose). Spikelets erect, spreading.

Hermaphrodite (`perfect') spikelets. Hermaphrodite spikelets pedicellate, 8-14(-17) mm long, not disarticulating as a separate unit, disarticulating above the glumes. Pedicels to 20 mm long. Glumes two per spikelet, dissimilar (often purple in the centre), subequal to unequal in length, shorter than the florets, slightly shorter than the proximal lemma (?). Lower glume narrowly ovate to ovate, 3.8-6.3(-7) mm long, 1.2-2.1 mm wide, weakly keeled, acute, muticous, margin hyaline; 3(-5) veined; intercostal regions glabrous. Upper glume narrowly ovate to ovate, (4.6-)6.4-7.5(-8) mm long, 1.7-3 mm wide, weakly keeled, acute, margin hyaline; 5(-7) veined, midvein glabrous; intercostal regions glabrous. Hermaphrodite florets 2-5(-6) per spikelet. Rachilla disarticulating between the florets, disarticulating directly below the florets, segments bearded at the apex, apically prolonged; terminated by a rudimentary floret. Callus present, blunt, hirsute (?). Lemma 5.9-8.4(-9) mm long, acute, dentate (although initially entire, veins not extending to the margin), 2(-4) -lobed (the teeth 0.26-0.36 mm long, the outer teeth shorter), awned. Lemma margins smooth (initially open but later tightly inrolled, concealing the palea and constricting the apex). Lemma 5-7 veined. Lemma veins scabrous, with the hairs on the midvein; intercostal regions papillose to scabrous. Awns 1. Median awn much longer than the body of the lemmas (often pigmented), 13.8-25.5 mm long, 1 veined, dorsal, arising from the upper half of the lemma (1/4-1/3 of the lemma length from the tip), geniculate, column twisted, scabrous. Palea fully developed, slightly shorter than the lemmas, 2-keeled, keels wingless, acute, bidentate (?); 2 veined, veins ciliate; intercostal regions glabrous and intercostal regions papillose. Lodicules 2, free, hyaline, acute, smooth, lobed or with entire margins, with margin divisions lateral, glabrous. Stamens 3. Anthers 1.3-2.3 mm long.

Fruit. Fruit free from both lemma and palea, oblong, dorsiventrally compressed (dorsally), 2-3.5 mm long, glabrous (yellow-brown). Hilum 35-45% of the caryopsis, orange to red-brown. Embryo 10-20% the length of the caryopsis.

Distribution. Endemic. Tasmania, New South Wales, and Victoria.

Ecology. Helophytic to mesophytic (?); in open habitats. Grows on floodplains and banks of inland rivers, and in marshes and lagoons, and flowers in response to rain or flooding.

Vouchers. Specimens examined morphologically: Tas.: Barnbougle, Forsyer R., river flats with Phalaris arundinacea, 8 Jan. 1979, J.A.Carpenter (HO).

Classification. Pooideae; Poodae; Aveneae.

Previously often confused with A. nervosus.

References. Morphology: Jacobs & Lapinpuro (1986). Telopea 2: 718-719. Breeding system: Jacobs & Lapinpuro (1986). Telopea 2: 716; Morris 60 (1991). Taxonomy: Jacobs & Lapinpuro (1986) Telopea 2: 718. General: Jacobs & Lapinouro (1986) Telopea 2: 715-729. Illustrations: amphib40.gif

Cite this publication as:
C.M. Weiller, M.J. Henwood, J. Lenz and L. Watson (1995 onwards). `Pooideae (Poaceae) in Australia - Descriptions and Illustrations'. URL http://muse.bio.cornell.edu/delta/
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.

References and Acknowledgements